Question

4. Explain digital-to-analog converter 5. What is a transducer ? Provide an example 6. What is an actuator? Provide an example

Answer 1

4.

Digital to analog converting is a process where digital signals that have a few (usually two) defined states are turned into analog signals, which have a theoretically infinite number of states. A Digital to Analog Converter, or DAC, is an electronic device that converts a digital code to an analog signal such as a voltage, current, or electric charge. Signals can easily be stored and transmitted in digital form; a DAC is used for the signal to be recognized by human senses or non-digital systems. Converting a signal from digital to analog can degrade the signal. Therefore details are chosen so that errors are negligible.

For example, take the below DSP illustration, an ADC converts the analog data collected by audio input equipment such as a microphone (sensor), into a digital signal that can be processed by a computer. The computer may add sound effects. Now a DAC will process the digital sound signal back into the analog signal that is used by audio output equipment such as a speaker.

Microphones Receiver Digtal Signal Processing A/D DSP Input Signal Output Signal Analog G:nary (Digital) Analog

5.

A transducer is a device that converts energy from one form to another. Usually a transducer converts a signal in one form of energy to a signal in another.Transducers are often employed at the boundaries of automation, measurement, and control systems, where electrical signals are converted to and from other physical quantities (energy, force, torque, light, motion, position, etc.). The process of converting one form of energy to another is known as transduction. For example,

OPulley Bourdon tube Output voltage Fixed TIIT end 2 LVDT Pressure

Here a lttle displacemet in Bourdon tube disturb the string and hence rotate pulley that further dispace the magnet in the coil. This motion of magnet induce current that turn into the signal due to the circuit involved. Basically, vibrational energy of the plunger in Bourdon tube is changed in detectable electrical energy.

6.

An actuator is a component of a machine that is responsible for moving and controlling a mechanism or system, for example by actuating (opening or closing) a valve; in simple terms, it is a "mover". An actuator requires a control signal and a source of energy. The control signal is relatively low energy and may be electric voltage or current, pneumatic or hydraulic pressure, or even human power. When the control signal is received, the actuator responds by converting the energy into mechanical motion. For example,
Left Cylinder (Area of Cylinder Right Cylinder Area of Cylinder 10 sq cm) Pump Piston O www.robotplatioral.co Hydraulic Actuator

the above diagram is of an actuator that work on principe of hydraulics.